Device and method for producing an edge-lit-hologram, edge-lit-hologram and lighting device for a vehicle

Abstract

A device for producing an edge-lit-hologram having a light source, in particular a laser light source, for generating a light beam, optical splitter for splitting the light beam generated by the light source into an object beam and a reference beam, imprinter for imprinting computer-generated information pertaining to the edge-lit-hologram to the object, optics for overlapping the object beam and the reference beam on or in a photosensitive recording medium for imprinting the edge-lit-hologram, where the optics include at least one transparent body through which the reference beam enters the photosensitive recording medium during operation of the device. The at least one transparent body shaped and disposed in the device such that the reference beam enters the body at an angle of less than 10° to the normal on the surface of the body or enters the body perpendicular to the surface of the body.

What is claimed is: 
     
       1. A device for producing an edge-lit-hologram, the device comprising:
 a light source or a laser light source to generate a light beam; 
 an optical splitter to split the light beam generated by the light source into an object beam and a reference beam; 
 an imprinter to imprint, to the object beam, computer-generated information pertaining to the edge-lit-hologram; and 
 optics for overlapping the object beam and the reference beam on or in a photosensitive recording medium for imprinting the edge-lit-hologram, 
 wherein the optics comprise at least one transparent body through which the reference beam enters the photosensitive recording medium during operation of the device, 
 wherein the at least one transparent body is shaped and disposed in the device such that the reference beam enters the at least one transparent body at an angle of less than 10° to the normal on a surface of the at least one transparent body or enters the at least one transparent body perpendicular to the surface of the at least one transparent body, and 
 wherein the device further comprises a transparent substrate on which the photosensitive recording medium is disposed, the transparent substrate being positioned between the at least one transparent body and the photosensitive recording medium. 
 
     
     
       2. The device according to  claim 1 , wherein the optics for overlapping the object beam and the reference beam further comprises a reflector from which the reference beam is reflected onto the at least one transparent body during operation of the device, the reflector being a concave parabolic reflector. 
     
     
       3. The device according to  claim 2 , wherein mutually facing surfaces of the reflector and the at least one transparent body correspond to each other or are similarly shaped, wherein a surface of the reflector facing the at least one transparent body is concave or parabolically concave, and wherein the surface of the at least one transparent body facing the reflector is convex or spherically convex. 
     
     
       4. The device according to  claim 1 , wherein the at least one transparent body comprises two transparent bodies through which the reference beam is adapted to enter the photosensitive recording medium, wherein the two transparent bodies are disposed on sides of the transparent substrate facing away from each other. 
     
     
       5. The device according to  claim 1 , further comprising an immersion agent or an immersion liquid, which is disposed between the at least one transparent body and the photosensitive recording medium or between the at least one transparent body and the transparent substrate. 
     
     
       6. The device according to  claim 1 , wherein the optics for overlapping the object beam and the reference beam further comprises a reflector, and wherein the photosensitive recording medium together with the transparent substrate are adapted to be moved relative to the at least one transparent body and the reflector. 
     
     
       7. The device according to  claim 1 , wherein the optics for overlapping the object beam and the reference beam are designed such that an angle of incidence at which the reference beam impinges upon a surface of a first portion of the recording medium is different from an angle of incidence at which the reference beam impinges upon a surface of a second portion of the recording medium. 
     
     
       8. A method for producing an edge-lit-hologram using the device according to  claim 1 , the method comprising:
 providing the photosensitive recording medium on the transparent substrate, so that the transparent substrate is positioned between the at least one transparent body and the photosensitive recording medium; 
 generating the reference beam; 
 generating the object beam; 
 imprinting computer-generated information pertaining to the edge-lit-hologram to the object beam; and 
 overlapping the object beam and the reference beam on or in the photosensitive recording medium for imprinting the edge-lit-hologram, 
 wherein the optics include the at least one transparent body through which the reference beam enters the photosensitive recording medium, and 
 wherein the at least one transparent body is shaped and disposed in the device such that the reference beam enters the at least one transparent body at an angle of less than 10° to the normal on the surface of the at least one transparent body or enters the at least one transparent body perpendicular to the surface of the at least one transparent body. 
 
     
     
       9. The method according to  claim 8 , wherein successively a plurality of portions of the photosensitive recording medium are simultaneously impinged upon with the object beam and the reference beam to produce a plurality of sub-holograms, wherein an angle of incidence at which the reference beam impinges on a surface of a first portion of the recording medium is different from an angle of incidence at which the reference beam impinges on a surface of a second portion of the recording medium. 
     
     
       10. The method according to  claim 8 , wherein the photosensitive recording medium is moved between an exposure with the object beam and the reference beam for generating a first sub-hologram at the first portion of the recording medium and an exposure with the object beam and the reference beam for generating a second sub-hologram at a second portion of the recording medium in a plane parallel to the planar surface of the recording medium. 
     
     
       11. The method according to  claim 10 , wherein the optics for overlapping the object beam and the reference beam further comprises a reflector, and wherein the photosensitive recording medium together with the transparent substrate is moved relative to the at least one transparent body and the reflector. 
     
     
       12. The method according to  claim 8 , wherein the produced edge-lit-hologram serves as a master hologram for the production of hologram replicas. 
     
     
       13. An edge-lit hologram, produced with a device according to  claim 1 , wherein the edge-lit-hologram is provided to a curved surface and for use with a light source having a predetermined divergence. 
     
     
       14. A lighting device for a vehicle comprising the edge-lit-hologram according to  claim 13 , wherein the lighting device includes a curved surface on which the edge-lit-hologram is disposed. 
     
     
       15. The method according to  claim 8 , wherein the edge-lit-hologram is a computer-generated edge-lit-hologram. 
     
     
       16. The device according to  claim 1 , wherein the edge-lit-hologram is a computer-generated edge-lit-hologram.